1. Field of the Invention
The present invention relates to a method and apparatus for ablation of the cornea with a laser and in particular relates to sculpturing prism lens into the cornea to correct strabismus (non-alignment of the optical axes).
2. Description of the Prior Art
It is known in the art to use an excimer laser to sculpture the human cornea in order to correct a refractive error. U.S. Pat. No. 4,665,913 entitled "Method for Ophthalmological Surgery" invented by Francis L'Esperance teaches ablative photo decomposition to change the front surface of the cornea from greater to a lesser spherical curvature or from a lesser to greater spherical curvature. This procedure change the refractive error thus effecting reduction in a myopic or in a hyperopic condition. U.S. Pat. No. 4,798,204 also issued to L'Esperance teaches a technique of sculpturing the epithelium-free Bowman's membrane of the cornea to achieve a corrected-curvature profile.
The prior art does not teach how to correct strabismus (non-alignment of the optical axes) by laser sculpturing. Only changes in curvature effecting refractive error is taught. The prior art does not teach shaping a prism lens on the cornea.